On 05/05/2021 15:41, Janusz Krzysztofik wrote:
IGT i915/perf library functions now always operate on sysfs perf
attributes of card0 device node, no matter which DRM device fd a user
passes. The intention was to always switch to primary device node if
a user passes a render device node fd, but that breaks handling of
non-card0 devices.
If a user passed a render device node fd, find a primary device node of
the same device and use it instead of forcibly using the primary device
with minor number 0 when opening the device sysfs area.
v2: Don't assume primary minor matches render minor with masked type.
Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@xxxxxxxxxxxxxxx>
Cc: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx>
---
lib/i915/perf.c | 31 ++++++++++++++++++++++++++++---
1 file changed, 28 insertions(+), 3 deletions(-)
diff --git a/lib/i915/perf.c b/lib/i915/perf.c
index 56d5c0b3a..d7768468e 100644
--- a/lib/i915/perf.c
+++ b/lib/i915/perf.c
@@ -372,14 +372,39 @@ open_master_sysfs_dir(int drm_fd)
{
char path[128];
struct stat st;
+ int sysfs;
if (fstat(drm_fd, &st) || !S_ISCHR(st.st_mode))
return -1;
- snprintf(path, sizeof(path), "/sys/dev/char/%d:0",
- major(st.st_rdev));
+ snprintf(path, sizeof(path), "/sys/dev/char/%d:%d", major(st.st_rdev), minor(st.st_rdev));
+ sysfs = open(path, O_DIRECTORY);
Just to spell out the error paths :
if (sysfs < 0)
return sysfs;
- return open(path, O_DIRECTORY);
+ if (sysfs >= 0 && minor(st.st_rdev) >= 128) {
Then just if (minor(st.st_rdev) >= 128) { ...
Maybe add a comment above this is : /* If we were given a renderD*
drm_fd, find it's associated cardX node. */
+ char device[100], cmp[100];
+ int device_len, cmp_len, i;
+
+ device_len = readlinkat(sysfs, "device", device, sizeof(device));
+ close(sysfs);
+ if (device_len < 0)
+ return device_len;
+
+ for (i = 0; i < 128; i++) {
+
+ snprintf(path, sizeof(path), "/sys/dev/char/%d:%d", major(st.st_rdev), i);
+ sysfs = open(path, O_DIRECTORY);
+ if (sysfs < 0)
+ continue;
+
+ cmp_len = readlinkat(sysfs, "device", cmp, sizeof(cmp));
+ if (cmp_len == device_len && !memcmp(cmp, device, cmp_len))
+ break;
+
+ close(sysfs);
You might want to set sysfs = -1 here just in the unlikely case this is
never found.
+ }
+ }
+
+ return sysfs;
}
struct intel_perf *
With the proposed changes :
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx>
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
